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US4486682A
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Stress compensated quartz resonator having ultra-linear frequency-temperature response
Assignee: United States Department of the Army
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Filing: 1983-03-17
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Granted: 1984-12-04
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Expires: 2003-03-17
Abstract
Abstract A new family of stress compensated quartz resonators having cuts exhibiting an ultra-linear frequency vs. temperature characteristic. This family of resonators has an orientation defined with respect to the crystallographic axes by polar angles φ and θ, which angles lie on the locus where the second-order temperature coefficient of frequency is zero between the angles φ=20°±2° and θ=20°±5°, and in close proximity to the locus of zero coefficient of stress. In one preferred embodiment, the resonator comprises a plate whose angles of cut φ and θ are both substantially equal to 20°. In a second preferred embodiment an exact stress compensation is provided where φ is substantially equal to 20.8° and θ is substantially equal to 23.2°, and orientation where the locus of the zero coefficient of stress intersects the locus of the zero of the second-order temperature coefficient.
Inventors
- 👤 Mitsuo Nakazawa
- 👤 Arthur Ballato
- 👤 Theodore J. Lukaszek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:54
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/02007; H03H9/02015; H03H9/02023; H03H9/02086; H03H9/02133
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
148 words
A piezoelectric resonator comprising a monolithic thin plate of piezoelectric material having a doubly rotated cut positioned at an orientation with respect to a standard rotational symbol YXwl (φ,θ) defined in terms of the X, Y, Z crystallographic axes and the major faces at polar angles φ and θ, wherein thickness is in the Y direction, length in the X direction and width in the Z direction, and wherein φ is the direction of first rotation about the Z axis with respect to the X axis and θ is the direction of second rotation about the X axis with respect to the Z axis, where angle φ is in the range of φ=20°±2° C. and where angle θ is in the range of θ=20°±5° C. and are on a locus such that the second order temperature coefficient of frequency approximates zero and the coefficient of stress approximates zero.
Claim 2
Dependent Claim
148 words
A piezoelectric resonator comprising a monolithic thin plate of piezoelectric material having a doubly rotated cut positioned at an orientation with respect to a standard rotational symbol YXwl (φ,θ) defined in terms of the X, Y, Z crystallographic axes and the major faces at polar angles φ and θ, wherein thickness is in the Y direction, length in the X direction and width in the Z direction, and wherein φ is the direction of first rotation about the Z axis with respect to the X axis and θ is the direction of second rotation about the X axis with respect to the Z axis, where angle φ is in the range of φ=20°±2° C. and where angle θ is in the range of θ=20°±5° C. and are on a locus such that the second order temperature coefficient of frequency approximates zero and the coefficient of stress approximates zero.
Claim 3
Dependent Claim
21 words
The piezoelectric resonator as defined by claim 1 wherein said thin plate of piezoelectric material comprises a thin plate of quartz.
Claim 4
Dependent Claim
25 words
The piezoelectric resonator as defined by claim 2 wherein said angle φ is substantially equal to 20° and wherein said angle θ is substantially 20°.
Claim 5
Dependent Claim
52 words
The piezoelectric resonator as defined by claim 2 wherein said angle φ is substantially 20.8° and said angle θ is substantially 23.2°, an orientation where the locus of the zero coefficient of stress intersects the locus of the second order temperature coefficient and thus providing a resonator having a precise stress compensation.
Claim 6
Dependent Claim
147 words
A piezoelectric resonator comprising a thin plate of quartz operable at a predetermined harmonic and having a doubly rotated cut positioned at an orientation with respect to a standard rotational symbol YXwl (φ,θ) defined in terms of the X,Y,Z crystallographic axes and the major faces at polar angles of φ and θ, wherein thickness is in the Y direction, length in the X direction and width in the Z direction, and wherein φ is the direction of first rotation about the Z axis with respect to the X axis and θ is the direction of second rotation about the X axis with respect to the Z axis, where φ is in the range of φ=20°±2° and θ is in the range of θ=20°±5°, said angles being on a locus such that the second order temperature coefficient of frequency approximates zero and the coefficient of stress approximates zero.
Claim 7
Dependent Claim
147 words
A piezoelectric resonator comprising a thin plate of quartz operable at a predetermined harmonic and having a doubly rotated cut positioned at an orientation with respect to a standard rotational symbol YXwl (φ,θ) defined in terms of the X,Y,Z crystallographic axes and the major faces at polar angles of φ and θ, wherein thickness is in the Y direction, length in the X direction and width in the Z direction, and wherein φ is the direction of first rotation about the Z axis with respect to the X axis and θ is the direction of second rotation about the X axis with respect to the Z axis, where φ is in the range of φ=20°±2° and θ is in the range of θ=20°±5°, said angles being on a locus such that the second order temperature coefficient of frequency approximates zero and the coefficient of stress approximates zero.
Claim 8
Dependent Claim
21 words
The piezoelectric resonator as defined by claim 5 wherein said thin plate of quartz is operable at a predetermined odd harmonic.
Claim 9
Dependent Claim
20 words
The piezoelectric resonator as defined by claim 5 wherin said thin plate of quartz is operable at two harmonics simultaneously.
References Cited (Backward Citations)
US4313071A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-04 | 1988-06-04 | 1988-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-04 | 1992-06-04 | 1992-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-04 | 1996-06-04 | 1996-12-04 | $7700.00 | Window Closed / Lapsed |